Medical Benefits of Weight Loss
If you are overweight, you are not alone. In 2007, 2 out of 3 Americans are overweight or obese. As a society, we are becoming increasingly mindful that decreased activity coupled with increased caloric intake and poor nutrition slowly but inevitably overwhelm our bodies’ ability to maintain a healthy weight.
Being overweight or obese puts you at serious risk for developing many obesity related diseases. That’s the bad news. The good news is that reducing your weight dramatically reduces these same risks. For those patients who suffer from these conditions, weight loss can significantly improve or completely correct these conditions.
Insulin Resistance and Diabetes Mellitus
Obesity leads to insulin resistance, a diminished biological response to the hormone insulin. This resistance is characterized by an elevation of circulating insulin, a diminished ability to store glucose, and a propensity to store fat.
In patients with non-insulin-dependent diabetes mellitus, serum glucose levels improve within days after starting a weight loss program. One study showed that the average fasting blood glucose levels in persons with type 2 diabetes decreased from 290 mg/dL to 110 mg/dL in 3 days in response to a very low calorie diet (1). Medication (oral agents or insulin) can be greatly reduced or eliminated in such cases (2). Another study reported that, after a 23-kg weight loss (22% of initial body weight), all patients taking oral agents and 82% of patients taking insulin were able to discontinue medication (3). Similar results were reported with weight losses of 9.3 kg (4). In general, patients with a 15% reduction in total body weight may consider stopping oral agents. (5). Smaller decreases in total body weight may even cure “pre-diabetes”, a significant cardiovascular risk.
Hypertension
Hypertension improves with weight loss in overweight persons. In patients following Very Low Calorie Diets (VLCD’s), one study reported a significant decrease in systolic blood pressure in 81% of patients and in diastolic pressure in 62% of patients (6). Patients receiving a diet of 800 to 1200 kcal (typical for Jumpstart patients) who averaged a weight loss of 10.5 kg showed decreases in both systolic and diastolic pressures of about 20 mm Hg. In about three quarters of these patients, blood pressure returned to normal. (7) Adding an exercise regimen to weight loss lead to even greater improvements in blood pressure.
Dyslipidemia
Obesity is often associated with an elevation of serum triglycerides and total cholesterol. The ratio of LDL to HDL cholesterol is usually elevated, resulting in an even greater risk of heart attacks and strokes. All of these values generally improve with weight loss. Often, fasting triglyceride levels that may be as high as 1000 to 1500 mg/dL will return to normal levels (<250 mg/dL) with dietary treatment alone. Weight loss has been repeatedly reported to increase HDL (“good”) cholesterol levels. Even rather small weight losses of 5% to 10% of initial weight will have this result. (8)
Sleep Apnea
Obesity can be associated with mild to severe respiratory functional impairment. Increasing obesity is associated with decreasing oxygen saturation. Two primary disorders ensue: obesity-hyperventilation syndrome and sleep apnea.
Patients with hypoxemia (low blood oxygen levels) and sleep apnea improve quickly with weight reduction. For every 1 percent decrease in weight, sleep apnea patients decrease their apnea-hypopnea indices (the amount they stop breathing at night) by 3 percent (9). In fact, many sleep apnea patients who sleep with CPAP machines are able to stop using their breathing machines at night after weight loss.
A disturbance of ventilation-perfusion (a mismatch in breathing vs. circulation) is common in obese persons. This disturbance can result in heart failure. These conditions also improve with weight loss. With significant weight loss, essentially normal pulmonary function can be achieved and cardiac function can be normalized.
Metabolic Syndrome
Intra-abdominal fat is metabolically active and associated with serious health risk. Metabolic Syndrome describes a cluster of cardiovascular risk factors which combine to produce a pro-inflammatory and pro-thrombotic (hypercoagulable) state. This condition leads to vascular diseases that result in heart attacks and strokes and a pro-inflammatory state associated with an increased incidence of a number of cancers. It is estimated that over 50 million Americans are currently at risk, but that less than 5% are diagnosed. (10).
To qualify for Metabolic Syndrome, one needs 3 out of 5 of the following components: 1. increased intra-abdominal fat defined by a waist circumference greater than 40 inches in men and 35 inches in women 2. high blood pressure 3. elevated triglycerides 4. low HDL cholesterol 5. diabetes or pre-diabetes. Abdominal obesity is present in 84% of patients with Metabolic Syndrome.
In summary, fat location matters. Intra-abdominal fat is metabolically active and dangerous and can lead to heart attacks, strokes, cancers, and more. Fortunately, 1st-line treatment for Metabolic Syndrome is weight reduction and increased physical activity. (11). Waist circumference and intra-abdominal fat decrease markedly with the type of weight loss typically experienced by patients at Jumpstart Medicine.
Polycystic Ovarian Syndrome
Polycystic Ovarian Syndrome (PCOS) affects 5 – 10% of reproductive age women. It occurs in association with obesity, type 2 diabetes, and anovulatory infertility. As noted above, weight loss improves diabetes. Weight loss in PCOS patients can also significantly improve their reproductive potential (fertility).
Degenerative Joint Disease
Low back pain and osteoarthritis of the knee are both more common in obese persons. Obese women are 4 times more likely and obese men 5 times more likely to develop osteoarthritis of the knees (NHANES I). Fortunately, the associated knee pain and disability improve or resolve with weight loss. According to the Framingham Study, an 11 pound weight loss in women decreased their risk for knee osteoarthritis by 50%. The degree of improvement varies with the amount of structural damage but relief can oftentimes be complete with moderate weight loss.
Social Stigmatization and Prejudice
In addition to suffering from health risks, obese individuals also suffer discrimination and decreased competitiveness in our society. Compared to a normal weight counterpart with otherwise equal credentials, an obese person is less likely to be hired for a job and more likely to be paid less if he or she receives the job. Obese individuals are less likely to be admitted to competitive colleges than their otherwise equal normal weight candidates.
Other Benefits
Because the risks attending general surgical procedures are greater in obese patients, it is often beneficial to reduce a patient’s weight before attempting a major elective procedure such as an orthopedic operation, cholecystectomy, or gastric bypass. A 5% to 10% reduction in body weight or a 5-unit change in body mass index (BMI) can reduce the duration of hospitalization and the incidence of postoperative complications (12).
- Henry RR, Wiest-Kent TA, Scheaffer L, Kolterman OG, Olefsky JM. Metabolic consequences of very-low-calorie diet therapy in obese non-insulin-dependent diabetic and nondiabetic subjects. Diabetes. 1986; 35:155-64
- Anderson JW, Hamilton CC, Brinkman-Kaplan V. Benefits and risks of an intensive very-low-calorie diet program for severe obesity. Am J Gastroenterol. 1992; 87:6-15.
- Kirschner MA, Schneider G, Ertel NH, Gorman J. An eight-year experience with a very-low-calorie formula diet for control of major obesity. Int J Obes. 1988; 12:69-80.
- Fitz JD, Sperling EM, Fein HG. A hypocaloric high-protein diet as primary therapy for adults with obesity-related diabetes: effective long-term use in a community hospital. Diabetes Care. 1983; 6:328-33.
- Wing et al., Arch Int Med 1987; 147:1749.
- MacMahon S, Cutler J, Brittain E, Higgins M. Obesity and hypertension: epidemiological and clinical issues. Eur Heart J. 1987; 8(Suppl B):57-70.
- Reisin E, Abel R, Modan M, Silverberg DS, Eliahou HE, Modan B. Effect of weight loss without salt restriction on the reduction of blood pressure in overweight hypertensive patients. N Engl J Med. 1978; 298:1-6.
- Wolf RN, Grundy SM. Influence of weight reduction on plasma lipoproteins in obese patients. Arteriosclerosis. 1983; 3:160-9.
- Peppard et al. Longitudinal study of moderate weight change and sleep-disordered breathing. JAMA 2000;284(23)3015-3021.
- Ford ES et al. Prevalence of the Metabolic Syndrome Among U.S. Adults. JAMA 2002; 287: 356-59.
- Expert Panel on Detection, Evaluation, and Treatment of High Cholesterol in Adults, JAMA 2001; 285: 2486-2497.
- Pasulka PS, Bistrian BR, Benotti PN, Blackburn GL. The risks of surgery in obese patients. Ann Intern Med. 1986; 104:540-6.
